最简 jrtplib 收发数据实例

    jrtplib 的功能，在它的说明文档中有介绍：For applications such as a mixer or translator using the RTPSession class will not be a good solution. Other components can be used for this purpose: a transmission component, an SSRC table,an RTCP scheduler etc. Using these, it should be much easier to build all kinds of applications. 简单翻译过来就是它适合传输组件，SSRC表,RTCP调度等应用程序，但是并不适合做混合器和翻译器。

    在jrtplib的使用的时候，有下面的几点需要被别注意：

    （1）端口不能是奇数，否者运行时会出现错误：

        ERROR: The specified port base is not an even number

    （2）默认编译的jrtplib是没有打开宏RTP_SUPPORT_THREAD 

        也就是在接收数据的时候，它不会自动的查询是否接收到数据，需要在应用程序中添加轮询函数：sess.Poll()

jrtplib_receive.cpp 代码：

/*=============================================================================   *     FileName: jrtplib_receive.cpp   *         Desc: receive packet and print out the payloaddata     *       Author: licaibiao   *   LastChange: 2017-04-10   * =============================================================================*/#include <jrtplib3/rtpsession.h>#include <jrtplib3/rtpudpv4transmitter.h>#include <jrtplib3/rtpipv4address.h>#include <jrtplib3/rtpsessionparams.h>#include <jrtplib3/rtperrors.h>#include <jrtplib3/rtplibraryversion.h>#include <jrtplib3/rtppacket.h>#include <stdlib.h>#include <stdio.h>#include <iostream>#include <string>using namespace jrtplib;void checkerror(int rtperr){if (rtperr < 0){std::cout << "ERROR: " << RTPGetErrorString(rtperr) << std::endl;exit(-1);}}int main(void){RTPSession sess;uint16_t portbase = 6664;int status;bool done = false;RTPUDPv4TransmissionParams transparams;RTPSessionParams sessparams;sessparams.SetOwnTimestampUnit(1.0/10.0);sessparams.SetAcceptOwnPackets(true);transparams.SetPortbase(portbase);status = sess.Create(sessparams,&transparams);checkerror(status);sess.BeginDataAccess();RTPTime delay(0.020);RTPTime starttime = RTPTime::CurrentTime();while (!done){status = sess.Poll();checkerror(status);if (sess.GotoFirstSourceWithData()){do{RTPPacket *pack;while ((pack = sess.GetNextPacket()) != NULL){std::cout << pack->GetPayloadData() << std::endl;sess.DeletePacket(pack);}} while (sess.GotoNextSourceWithData());}RTPTime::Wait(delay);RTPTime t = RTPTime::CurrentTime();t -= starttime;if (t > RTPTime(60.0))done = true;}sess.EndDataAccess();delay = RTPTime(10.0);sess.BYEDestroy(delay,0,0);    return 0;}

    上面程序，以每0.02s的周期去查询是否有接收到数据，持续60s，接收到数据之后，将接收到的数据通过标准输出打印出来。

jrtplib_send.cpp 代码：

/*=============================================================================   *     FileName: jrtplib_send.cpp   *         Desc: sending packets to  destination port     *       Author: licaibiao   *   LastChange: 2017-04-10   * =============================================================================*/#include <jrtplib3/rtpsession.h>#include <jrtplib3/rtpudpv4transmitter.h>#include <jrtplib3/rtpipv4address.h>#include <jrtplib3/rtpsessionparams.h>#include <jrtplib3/rtperrors.h>#include <jrtplib3/rtplibraryversion.h>#include <stdlib.h>#include <stdio.h>#include <iostream>#include <string>using namespace jrtplib;void checkerror(int rtperr){if (rtperr < 0){std::cout << "ERROR: " << RTPGetErrorString(rtperr) << std::endl;exit(-1);}}int main(void){    int i;    int num;int status;    RTPSession sess;uint16_t portbase = 6666;      uint16_t destport = 6664;#if 0uint32_t destip;destip    = inet_addr("192.168.0.6"); if (destip == INADDR_NONE){std::cerr << "Bad IP address specified" << std::endl;return -1;}destip = ntohl(destip);#elseuint8_t destip[]={192,168,0,6};#endif     std::cout << "Number of packets you wish to be sent:" << std::endl;std::cin >> num;RTPUDPv4TransmissionParams transparams;RTPSessionParams sessparams;sessparams.SetOwnTimestampUnit(1.0/10.0);sessparams.SetAcceptOwnPackets(true);transparams.SetPortbase(portbase);status = sess.Create(sessparams,&transparams);checkerror(status);RTPIPv4Address addr(destip,destport);status = sess.AddDestination(addr);checkerror(status);for (i = 1 ; i <= num ; i++){printf("\nSending packet %d/%d\n",i,num);status = sess.SendPacket((void *)"1234567890",10,0,false,10);checkerror(status);RTPTime::Wait(RTPTime(1,0));}sess.BYEDestroy(RTPTime(10,0),0,0);    return 0;}

    上面程序，通过标准输入确定需要发送数据的包数，然后以1s的周期发送数据。这里是p2p传输，发送之前需要指定发送地址和发送端口。这里的地址就是接收端主机的IP地址，这里的目的端口，就是接收端程序设置的本地端口。

Makefile文件：

APP = testLINK_OPTS = -ljrtpOBJ  = jrtplib_receive.cpp#OBJ  = jrtplib_send.cppout: g++ $(OBJ) -o $(APP)  $(LINK_OPTS)clean:rm -rf *o $(APP)

编译执行部分结果：

发送端：

licaibiao@lcb:~/test/RTP/test_jrtplib$ ./test Number of packets you wish to be sent:100Sending packet 1/100Sending packet 2/100Sending packet 3/100Sending packet 4/100Sending packet 5/100Sending packet 6/100

接收端：

licaibiao@ubuntu:~/test/RTP_TEST/JRTPLIB/biao$ ./test 12345678901234567890123456789012345678901234567890123456789012345678901234567890 

    注意：在编译运行本程序之前，需要正确安装好jrtplib 

   工程代码可在这里下载：最简jrtplib 收发数据实例